BLIND SHAFT: Drama. Directed by Li Yang. In Mandarin with English subtitles. (Not rated. 92 minutes. At the Opera Plaza and Rafael.)

The illegal Chinese coal mines of "Blind Shaft" are fraught with danger. This is especially true of mines employing two men named Song and Tang. Partners in crime, they kill co-workers, present the murders as accidents and collect settlements under the table.

The murder-plot angle is never completely plausible, but filmmaker Li Yang overcomes it with a searing depiction of economic desperation and moral alienation. Li's film condemns China's deadly unregulated mines (they still kill thousands per year) but does so subtly, through good storytelling rather than righteousness. "Blind Shaft" offers a workaday look at how circumstances can turn men into monsters.

Shot documentary style in 16 millimeter, the picture follows the criminals as they don hard hats and descend, via crude equipment, into physical and spiritual depths. After the film's first "accident," Tang (played as an affable sociopath by Wang Shuangbao) scoffs at the paltry sum offered for the victim he claims is his brother. But he accepts the payout, and the killers discuss the murder in the same blase manner with which they remove their work gloves.

The criminals ply their trade in cities where jobless men from the country, casualties of China's supposed economic boom, gather to look for work. The duo tells the men they can make good money in faraway mines. Glad to find any job, the suckers agree to pose as relatives of the miners.

Cynicism isn't contained to the killers. "China lacks everything," says one fat-cat boss. "The only thing it doesn't lack is people." Yet one of the killers shows traces of heart, even if his guilt is misplaced. The younger grifter, Song, laments visiting prostitutes instead of sending money back to his family. Li Yixiang invests the character with broiling inner conflict. His eruptions over mundane insults signal a growing distaste for the murder game.

Filmmaker Li ups the stakes by throwing a lamb in with the lions. As a 16- year-old boy trying to earn money for school, actor Wang Baoqiang has the face of an angel and a teenager's awkward vulnerability. When the kid calls Song "Uncle," Wang makes us feel he's starting to believe it. The boy's innocence further cracks Song's resolve, and his hardened cohort smells weakness.

Nagging the story throughout is the faulty concept of the killers' ruse. The men show up unannounced at job sites, so it's not as if the mine owners are expecting a team of relatives. Director Li never quite reconciles this aspect of the story, and it's the one slip in logic in a picture that otherwise has the ring of unfettered, tragic truth.